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berkelium

American  
[ber-kee-lee-uhm] / bərˈki li əm /

noun

Chemistry.
  1. a transuranic element. Bk; 97; 249 (?).


berkelium British  
/ bɜːˈkiːlɪəm, ˈbɜːklɪəm /

noun

  1. a metallic transuranic element produced by bombardment of americium. Symbol: Bk; atomic no: 97; half-life of most stable isotope, 247 Bk: 1400 years; valency: 3 or 4; relative density: 14 (est)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

berkelium Scientific  
/ bər-kēlē-əm,bûrklē-əm /
  1. A synthetic, radioactive metallic element of the actinide series that is produced from americium, curium, or plutonium. Its most stable isotope has a half-life of about 1,400 years. Atomic number 97; melting point 986°C; valence 3, 4.

  2. See Periodic Table


Etymology

Origin of berkelium

1945–50; named after Berkeley, California, where it was discovered; -ium